Over the last several years, microscopy as a scientific tool has reinvented itself It has changed from a group of principally descriptive methodologies, to a wide range of primary tools and techniques to investigate the molecular organization of organs, tissues and cells. Advances in microscope and camera design, fluorescent dye technology and the development of fluorescent proteins and multiple other novel imaging methods including 2 photon. Fluorescence Resonance Energy Transfer Microscopy (FRET), and Total Internal Reflection Fluorescence Microscopy (TIRF) have made the simultaneous resolution and quantitation of multiple concurrent molecular markers for both protein and DNA at a sub-micron resolution a reality. The recognition of the potential utility of these techniques to improve the scientific investigations of the rapidly expanding research community at the University of Pittsburgh Cancer Institute (UPCI) led to the formation of a centralized microscope imaging center; the Center for Biologic Imaging (CBI) at the University of Pittsburgh in 1991. The UPCI Cell and Tissue Imaging Facility (CTIF) was started as an offshoot of CBI eleven years ago. Since then the CTIF has become an essential resource for most ofthe research programs within UPCI. The CTIF described in this narrative performs microscopic analyses services for members of the UPCI research community, ranging from the traditional to the cutting edge, using a full complement of microscope technologies. At the time of the last review of this facility in 2003, UPCI had just relocated to the Shadyside campus. In order to ensure that outstanding microscopy services would be available for researchers in Shadyside, with support from UPCI, a satellite facility ofthe CTIF has been established in the Hillman Cancer Center specifically \o supply imaging capabilities to researchers at this location. The ability to establish and support the CTIF satellite facility has required a significant investment in instrumentation and personnel. We will use the CTIF support requested in this application to provide support for personnel who provide advanced microscopy support at the main CTIF center on the Oakland campus and also to provide resources for the new satellite facility in the Shadyside campus.